Regulation of tubulin gene expression during embryogenesis in Drosophila melanogaster.
Four different tubulins have been identified that are expressed during embryogenesis in Drosophila melanogaster. Two alpha-tubulin subunits (alpha 1 and alpha 2) and one beta-tubulin subunit (beta 1) are expressed throughout embryonic development. A second beta-tubulin subunit (beta 3) is expressed only for a short period in mid-embryonic development. Synthesis of beta 3-tubulin in vitro in a rabbit reticulocyte translation system is directed by RNA extracted from embryos only at the stage when the protein is expressed. Thus we conclude that the mRNA encoding beta 3-tubulin is transcribed only during the brief period of beta 3-tubulin synthesis. The expression of beta 3-tubulin is accompanied by a coordinate transient increase in the level of synthesis of the embryonic alpha-tubulins, thereby maintaining an approximately equimolar synthesis of alpha- and beta-tubulin subunits throughout embryogenesis.
D000818:Animals; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics*; D005786:Gene Expression Regulation; D007526:Isoelectric Point; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014404:Tubulin / Q000235:genetics*
D012333:RNA, Messenger; D014404:Tubulin